1. Field
One or more embodiments relate to an anode active material, an anode and a lithium battery including the anode active material, and a method of preparing the anode active material.
2. Description of the Related Technology
Lithium batteries are used in various applications due to their high voltage and high energy density characteristics. For example, because a large amount of electricity has to be charged or discharged and a prolonged operation is also necessary in the field of electric vehicles such as hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), a lithium battery having a high capacity, high rate characteristics, and excellent life characteristics is in demand.
The capacity of a battery using a carbon-based material is generally low due to a porous structure of carbon. For example, a theoretical capacity of graphite having high crystallinity is about 372 mAh/g for a LiC6 composition. Also, high rate characteristics of the carbon-based material are poor.
A metal that forms an alloy with lithium may be used as an anode active material having a high capacity in comparison to the carbon-based material. For example, metals that form an alloy with lithium are Si, Sn, Al, etc. However, metals that form alloys with lithium easily deteriorate and thus life characteristics are poor. For example, in the case of Sn, Sn particles are electrically isolated by repeated aggregation and crushing processes during repeated charge and discharge.
Also, thermal runaway may occur in lithium batteries due to a short circuit or the like.
Therefore, a lithium battery having an improved discharging capacity, life characteristics, and thermal stability is in demand.